var Spry;
if (!Spry) Spry = {};
if (!Spry.Widget) Spry.Widget = {};

Spry.Widget.TabbedPanels = function(element, opts) {
    this.element = this.getElement(element);
    this.defaultTab = 0; // Show the first panel by default.
    this.tabSelectedClass = "TabbedPanelsTabSelected";
    this.tabHoverClass = "TabbedPanelsTabHover";
    this.tabFocusedClass = "TabbedPanelsTabFocused";
    this.panelVisibleClass = "TabbedPanelsContentVisible";
    this.focusElement = null;
    this.hasFocus = false;
    this.currentTabIndex = 0;
    this.enableKeyboardNavigation = false;
    Spry.Widget.TabbedPanels.setOptions(this, opts);

    // If the defaultTab is expressed as a number/index, convert
    // it to an element.
    if (typeof (this.defaultTab) == "number") {
        if (this.defaultTab < 0)
        { this.defaultTab = 0; }
        else {
            var count = this.getTabbedPanelCount();
            if (this.defaultTab >= count)
            { this.defaultTab = (count > 1) ? (count - 1) : 0; }
        }
        this.defaultTab = this.getTabs()[this.defaultTab];
    }

    // The defaultTab property is supposed to be the tab element for the tab content
    // to show by default. The caller is allowed to pass in the element itself or the
    // element's id, so we need to convert the current value to an element if necessary.

    if (this.defaultTab) {
        this.defaultTab = this.getElement(this.defaultTab);
    }
    this.attachBehaviors();
};

Spry.Widget.TabbedPanels.prototype.getElement = function(ele)
{
    if (ele && typeof ele == "string")
		return document.getElementById(ele);
	return ele;
};

Spry.Widget.TabbedPanels.prototype.getElementChildren = function(element)
{
	var children = [];
	var child = element.firstChild;
	while (child)
	{
		if (child.nodeType == 1 /* Node.ELEMENT_NODE */)
			children.push(child);
		child = child.nextSibling;
	}
	return children;
};

Spry.Widget.TabbedPanels.prototype.addClassName = function(ele, className)
{
	if (!ele || !className || (ele.className && ele.className.search(new RegExp("\\b" + className + "\\b")) != -1))
		return;
	ele.className += (ele.className ? " " : "") + className;
};

Spry.Widget.TabbedPanels.prototype.removeClassName = function(ele, className)
{
	if (!ele || !className || (ele.className && ele.className.search(new RegExp("\\b" + className + "\\b")) == -1))
		return;
	ele.className = ele.className.replace(new RegExp("\\s*\\b" + className + "\\b", "g"), "");
};

Spry.Widget.TabbedPanels.setOptions = function(obj, optionsObj, ignoreUndefinedProps)
{
	if (!optionsObj)
		return;
	for (var optionName in optionsObj)
	{
		if (ignoreUndefinedProps && optionsObj[optionName] == undefined)
			continue;
		obj[optionName] = optionsObj[optionName];
	}
};

Spry.Widget.TabbedPanels.prototype.getTabGroup = function()
{
	if (this.element)
	{
		var children = this.getElementChildren(this.element);
		if (children.length)
			return children[0];
	}
	return null;
};

Spry.Widget.TabbedPanels.prototype.getTabs = function()
{
	var tabs = [];
	var tg = this.getTabGroup();
	if (tg)
		tabs = this.getElementChildren(tg);
	return tabs;
};
Spry.Widget.TabbedPanels.prototype.getContentPanelGroup = function()
{
	if (this.element)
	{
		var children = this.getElementChildren(this.element);
		if (children.length > 1)
			return children[1];
	}
	return null;
};

Spry.Widget.TabbedPanels.prototype.getContentPanels = function()
{
	var panels = [];
	var pg = this.getContentPanelGroup();
	if (pg)
		panels = this.getElementChildren(pg);
	return panels;
};

Spry.Widget.TabbedPanels.prototype.getIndex = function(ele, arr)
{
	ele = this.getElement(ele);
	if (ele && arr && arr.length)
	{
		for (var i = 0; i < arr.length; i++)
		{
			if (ele == arr[i])
				return i;
		}
	}
	return -1;
};

Spry.Widget.TabbedPanels.prototype.getTabIndex = function(ele)
{
	var i = this.getIndex(ele, this.getTabs());
	if (i < 0)
		i = this.getIndex(ele, this.getContentPanels());
	return i;
};

Spry.Widget.TabbedPanels.prototype.getCurrentTabIndex = function()
{
	return this.currentTabIndex;
};

Spry.Widget.TabbedPanels.prototype.getTabbedPanelCount = function(ele)
{
	return Math.min(this.getTabs().length, this.getContentPanels().length);
};

Spry.Widget.TabbedPanels.addEventListener = function(element, eventType, handler, capture)
{
	try
	{
		if (element.addEventListener)
			element.addEventListener(eventType, handler, capture);
		else if (element.attachEvent)
			element.attachEvent("on" + eventType, handler);
	}
	catch (e) {}
};

Spry.Widget.TabbedPanels.prototype.cancelEvent = function(e)
{
	if (e.preventDefault) e.preventDefault();
	else e.returnValue = false;
	if (e.stopPropagation) e.stopPropagation();
	else e.cancelBubble = true;

	return false;
};



Spry.Widget.TabbedPanels.prototype.onTabMouseOver = function(e, tab) {
    if (tab.title == "4")
        this.addClassName(tab, this.tabHoverClass + "-4");
    else { this.addClassName(tab, this.tabHoverClass + "-" + tab.tabIndex); }
    return false;
};

Spry.Widget.TabbedPanels.prototype.onTabMouseOut = function(e, tab) {
    if (tab.title == "4")
    { this.removeClassName(tab, this.tabHoverClass + "-4"); }
    else { this.removeClassName(tab, this.tabHoverClass + "-" + tab.tabIndex); }
    return false;
};

Spry.Widget.TabbedPanels.prototype.onTabFocus = function(e, tab)
{
	this.hasFocus = true;
	this.addClassName(tab, this.tabFocusedClass);
	return false;
};

Spry.Widget.TabbedPanels.prototype.onTabBlur = function(e, tab)
{
	this.hasFocus = false;
	this.removeClassName(tab, this.tabFocusedClass);
	return false;
};


Spry.Widget.TabbedPanels.prototype.preorderTraversal = function(root, func)
{
	var stopTraversal = false;
	if (root)
	{
		stopTraversal = func(root);
		if (root.hasChildNodes())
		{
			var child = root.firstChild;
			while (!stopTraversal && child)
			{
				stopTraversal = this.preorderTraversal(child, func);
				try { child = child.nextSibling; } catch (e) { child = null; }
			}
		}
	}
	return stopTraversal;
};

Spry.Widget.TabbedPanels.prototype.addPanelEventListeners = function(tab, panel)
{
	var self = this;
	Spry.Widget.TabbedPanels.addEventListener(tab, "mouseover", function(e) { return self.onTabMouseOver(e, tab); }, false);
	Spry.Widget.TabbedPanels.addEventListener(tab, "mouseout", function(e) { return self.onTabMouseOut(e, tab); }, false);

	if (this.enableKeyboardNavigation)
	{
		// XXX: IE doesn't allow the setting of tabindex dynamically. This means we can't
		// rely on adding the tabindex attribute if it is missing to enable keyboard navigation
		// by default.

		// Find the first element within the tab container that has a tabindex or the first
		// anchor tag.
		
		var tabIndexEle = null;
		var tabAnchorEle = null;

		this.preorderTraversal(tab, function(node) {
			if (node.nodeType == 1 /* NODE.ELEMENT_NODE */)
			{
				var tabIndexAttr = tab.attributes.getNamedItem("tabindex");
				if (tabIndexAttr)
				{
					tabIndexEle = node;
					return true;
				}
				if (!tabAnchorEle && node.nodeName.toLowerCase() == "a")
					tabAnchorEle = node;
			}
			return false;
		});

		if (tabIndexEle)
			this.focusElement = tabIndexEle;
		else if (tabAnchorEle)
			this.focusElement = tabAnchorEle;

		if (this.focusElement)
		{
			Spry.Widget.TabbedPanels.addEventListener(this.focusElement, "focus", function(e) { return self.onTabFocus(e, tab); }, false);
			Spry.Widget.TabbedPanels.addEventListener(this.focusElement, "blur", function(e) { return self.onTabBlur(e, tab); }, false);
		}
	}
};

Spry.Widget.TabbedPanels.prototype.showPanel = function(elementOrIndex) {
    var tpIndex = -1;
    var cpIndex = -1;
    if (typeof elementOrIndex == "number")
    { tpIndex = elementOrIndex; }
    else {
        // Must be the element for the tab or content panel.
        tpIndex = this.getTabIndex(elementOrIndex);
    }
    if (!tpIndex < 0 || tpIndex >= this.getTabbedPanelCount())
    { return; }
    var tabs = this.getTabs();
    var panels = this.getContentPanels();
    var numTabbedPanels = Math.max(tabs.length, panels.length);
    for (var i = 0; i < numTabbedPanels; i++) {
        if (i != tpIndex) {
            if (tabs[i]) {
                this.removeClassName(tabs[i], this.tabSelectedClass);
            }
            if (panels[i]) { this.removeClassName(panels[i], this.panelVisibleClass); }
        }
    }
    if (tabs[tpIndex].title == "4") {
        this.addClassName(tabs[tpIndex], this.tabSelectedClass + "-4");
    }
    else {
        this.addClassName(tabs[tpIndex], this.tabSelectedClass + "-" + elementOrIndex.tabIndex);
    }
    this.addClassName(panels[elementOrIndex.tabIndex], this.panelVisibleClass);

    this.currentTabIndex = tpIndex;
};

Spry.Widget.TabbedPanels.prototype.attachBehaviors = function(element)
{
	var tabs = this.getTabs();
	var panels = this.getContentPanels();
	var panelCount = this.getTabbedPanelCount();

	for (var i = 0; i < panelCount; i++)
		this.addPanelEventListeners(tabs[i], panels[i]);

	this.showPanel(this.defaultTab);
};